It's pretty easy to get your hands on a Medeco key. You don't need a blank, just any key, including one of the dozens of duplicates most building managers have. You'd just have to drill down further.

That said, I believe that Medeco locks are different in that two mechanisms have to be unlocked at the same time, namely the key has to be fully inserted before the traditional locking mechanism will operate, which doesn't make it unable to be bumped, but does make it more difficult.